The speech productin of both deaf and hard-of-hearing persons is hindered by problems with the /s/ phoneme and its voiced cognate /z/. The /s/ and /z/ sounds are very important in spoken English since they occur frequencly and carry such essential syntactic information as plural and possessive forms. Few hearing-impaired persons can regularly produce these sounds so that they are audible during conversational speech. Hearing-impaired speakers need a wearable device that will provide real-time feedback information on appropriate production of the /s/ and /z/ sounds. We propose to develop such a device that can be used in conjunction with a conventional hearing aid to vibrate the ear canal when s-sounds are detected in fluent speech. The specific goals of this research are: to develop a practical vibrotactile transducer from piezoelectric material that fits into the ear insert without interfering with normal functioning of a hearing aid and to develop a method for detection of the /s/ spectral pattern in fluent speech that can be implemented in a wearable, pocket-size unit. A secondary objective of this research is to study the general potential of earmold vibrators as an aid to the hearing handicapped when used in conjunction with a conventional hearing aid. The earmold vibrator to be developed under this proposal will be a significant step towads achieving an all-on-the-head system and would add a new demension to the help that can be provided for hearing handicapped patients.